The stop signal is produced in response to negative experiences at the food source and inhibits honey bee (Apis mellifera) waggle dancing. Here, we present a protocol for measuring the effects of an inhibitory signal associated with danger on honey bee dopamine levels. We describe steps for observing honey bee colonies, training them with artificial nectar, and simulating hornet attacks. We then detail procedures for recording waggle dancing and stop signals and measuring brain dopamine levels during different treatments. For complete details on the use and execution of this protocol, please refer to Dong et al.1.

Secondary inorganic aerosols play an important role in air pollution and climate change, and their formation modulates the atmospheric deposition of reactive nitrogen (including oxidized and reduced nitrogen), thus impacting the nitrogen cycle. Large-scale and long-term analyses of secondary inorganic aerosol formation based on model simulations have substantial uncertainties. Here we improve constraints on secondary inorganic aerosol formation using decade-long in situ observations of aerosol composition and gaseous precursors from multiple monitoring networks across the United States. We reveal a shift in the secondary inorganic aerosol formation regime in the rural United States between 2011 and 2020, making rural areas less sensitive to changes in ammonia concentrations and shortening the effective atmospheric lifetime of reduced forms of reactive nitrogen. This leads to potential increases in reactive nitrogen deposition near ammonia emission hotspots, with ecosystem impacts warranting further investigation. Ammonia (NH3), a critical but not directly regulated precursor of fine particulate matter in the United States, has been increasingly scrutinized to improve air quality. Our findings, however, show that controlling NH3 became significantly less effective for mitigating fine particulate matter in the rural United States. We highlight the need for more collocated aerosol and precursor observations for better characterization of secondary inorganic aerosols formation in urban areas.

Global warming will change the photosynthesis and transpiration of plants greatly and ultimately affect water use efficiency (WUE). Here, we present a protocol to investigate the response of maize WUE to the coupling effect of CO2 and temperature at ear stage using a specialized designed gradient. We describe steps for plant culture, parameter measurements, model fitting, and statistical analysis. This protocol holds potential for studying the response of WUE and CO2 adaptation across various plant species. For complete details on the use and execution of this protocol, please refer to Sun et al.1.

Approaches for detecting micro(nano)plastics (MNPs) released from intravenous infusion products (IVIPs) are vital for evaluating the safety of both IVIPs and their derived MNPs on human health, yet current understanding is limited. Here, we present a protocol for detecting polyvinyl chloride (PVC) MNPs by combining Raman spectroscopy, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDS), and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). We describe steps for collecting, pretreating, and measuring PVC MNPs released from IVIPs. For complete details on the use and execution of this protocol, please refer to Li et al.1.

Passive thermal management with zero-energy consumption and high compactness has drawn increasing attention. Here, we present a protocol to develop a hygroscopic salt-loaded heat sink with a moisture-permeable membrane encapsulation technique for electronics cooling. We describe steps for preparing lithium bromide solution and heat sink with anti-corrosion graphene coating. We then detail procedures for preparing the hygroscopic salt-loaded membrane-encapsulated heat sinks (HSMHSs). The produced low-cost HSMHS exhibits remarkably high thermal management performance without the risks of leakage and corrosion. For complete details on the use and execution of this protocol, please refer to Sui et al.1.

Recently, there has been a growing interest in using sustainable energy to decrease lignin monomers to generate high-value-added products. Here, we present a protocol for electrocatalytic hydrogenation of 5-hydroxymethylfurfural. We describe steps for catalyst preparation, performing electrocatalytic experiments, high-performance liquid chromatography analysis, and in situ infrared reflection-absorption spectroscopy testing. The synthesized catalyst used in this reaction exhibits enhanced selectivity and Faradaic efficiency in NaClO4 solution. For complete details on the use and execution of this protocol, please refer to Zhang et al.1.

Neighborhood physical disorder (PD), characterized by disruptions and irregularities in spatial elements, is associated with negative economic, social, and public health outcomes. Here, we present a protocol to quantitatively assess PD utilizing a range of metrics. We describe steps for collecting street views, constructing detection models using the YOLOv8 deep learning model, calculating PD scores, and quantifying changes in PD across streets and cites. This protocol serves as a methodological foundation for assessing PD in different countries and regions. For complete details on the use and execution of this protocol, please refer to Chen et al.1.

Amid a surge in waste volume, the need to achieve sustainable waste treatment has become increasingly important. Here, we present a protocol for the design and accelerated optimization of a waste-to-energy system using artificial intelligence tools. We describe steps for waste treatment process advancement as demonstrated by the medical waste-to-methanol conversion and implementing data-driven process optimization. We then detail procedures for streamlining tasks by establishing connectivity between systems such as Aspen Plus and MATLAB. For complete details on the use and execution of this protocol, please refer to Shi et al. (2022)1 and Fang et al. (2022).2.

The impact of climate change on economic inequality has attracted increasing attention from both government and academia. Here, we present a protocol for estimating both the impact of climate change on economic growth and economic growth inequality under multiple climate policies. We describe steps for constructing an uncertainty analysis framework, collecting and pre-processing data, and estimating the climate-economic response. We then detail procedures of predicting climate policy impact and calculating inter-country economic growth inequality. For complete details on the use and execution of this protocol, please refer to Tang et al. (2023).1.

In 2020, lockdown control measures were implemented to prevent a novel coronavirus disease 19 (COVID-19) pandemic in many places of the world, which largely reduced human activities. Here, we detect changes in weekly cycles of PM2.5, NO2, SO2, CO and O3 concentrations in 2020 compared to 2018 and 2019 using the observed data at 32 stations in Beijing. Distinct weekly cycles of annual average PM2.5, NO2, SO2 and CO concentrations existed in 2018, while the weekend effects changed in 2020. In addition, the weekly cycle magnitudes of PM2.5, NO2, SO2, and O3 concentrations in 2020 decreased by 29.60-69.26% compared to 2018, and 4.49-47.21% compared to 2019. We propose that the changing weekend effects and diminishing weekly cycle magnitudes may be tied to the COVID-19 lockdown controls, which changed human working and lifestyle cycles and reduced anthropogenic emissions of air pollutants on weekends more than weekdays.